Maths !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!111111

find the obtuse angle btwn the following pair of straight lines

1. y=( 2-√3)x+5 & y=(2+√3)x-7
2. y= -2 & y=x√3 -1


ans 135 of both

1.) y = (2-sqrt3)x+5
=> (2-sqrt3)x-y+5
i.e. m1 = -a/b=-(2-sqrt3)/-1
m1=(2-sqrt3)

again
y=(2+sqrt3)x-7
=> (2+sqrt3)x-y-7
i.e. m2= -a/b =-(2+sqrt3)/-1
m2=(2+sqrt3)

now,
angle between both line:
tanA=|(m1-m2) / (1+m1m2)|
tanA=|{(2-sqrt3)-(2+sqrt3)} / {1+(2-sqrt3)(2+sqrt3)}|
tanA=|-2sqrt3 / (1+4-3)|
tanA=|-sqrt3|
tanA=sqrt3
tanA=tan60
i.e. A=60
Obtuse angle = 180-60
=120
your answer 135 is wrong.

2.) y=-2
=> y+2=0
m1=-a/b =0/1=0
m1=0

y=xsqrt3-1
=> xsqrt3-y-1=0
m2=-a/b=-sqrt3/-1=sqrt3
m2=sqrt3

now you can solve with the help of above solution.

Answer of this question is also 120.

Good luck

1/ m1= ( 2- sqrt3)
m2 = ( 2+sqrt3)
tanA = m1-m1/1+ m1m2
tanA = 2 -sqrt3-2 -sqrt3/1+ (4-3)
tanA = - sqrt3
A = tan-1(-sqrt3) = 120 ==============
m1= 0 & m2 = sqrt3
tanA = m1- m2/1+m1m2
= sqrt3/1
A = tan-1(-sqrt3)=120
soboth are 120 deg